1. Field
Example embodiments of the presently described technology relate to information processing programs and information processing apparatuses. More specifically, present example embodiments relate to an information processing program and an information processing apparatus which detect a rotating operation on the basis of the changes of the positions (vector) designated by pointing devices, such as a touch panel, a tablet, a mouse, etc., obtains a controlled variable (signed scalar) from the detected rotating operation, and performs information processing on the basis of the obtained controlled variable.
2. Description of the Related Art
As conventional programs or apparatuses of such kind, one disclosed in Patent Laying-open No. 4-48318 (Patent Document 1) has been known. In the related art, a rotating operation respectively taking a first point (A) and a second point (B) as a starting point and an ending point is detected. Then, an angle between a direction from the reference point (O) to the first point and a direction from the reference point to the second point (rotation angle AOB) is obtained to scroll a screen by page by the amount corresponding to the obtained rotation angle.
Furthermore, one disclosed in Japanese Patent Laying-open No. 2002-222034 (Patent Document 2) has also been known. In the related art, a first point (A), a second point (B), a third point (C) . . . are sequentially detected. A displacement angle which a line segment BC forms with a line segment AB is first evaluated. Similarly, displacement angles between two adjacent line segments are sequentially obtained onward so as to be accumulated. Then, if the accumulated displacement angle is equal to or more than a threshold value, it is recognized that a rotating operation is performed to scroll the screen by the accumulated displacement angle.
However, as the related art in Patent Document 1, if the rotation angle AOB with respect to the reference point O is a controlled variable, even the same travel distance (operation amount) from the point A to the point B results in difference in the controlled variable depending on the distances from the reference point O to each of the points A and B. Thus, an operator has to adjust an operation amount by taking the distances from the reference point into consideration whenever he or she wants to perform a desired information processing.
On the other hand, as the related art in Patent Document 2, if the accumulated displacement angle is a controlled variable, until at least three points are detected, and the accumulated displacement angle above the threshold value is obtained, it is not recognized that a rotating operation is performed, and information processing is also not started. That is, a low response to the rotating operation occurs.